Dec 4th, 2008
NG Big idea: Many things in our world are mathematically similar and we can use this to understand and describe the world around us. Essential Question #2: What is the same and what is different about "similar" figures?
Vocabulary: Similar figures - Figures with the same shape. Two figures are mathematically similar if and only if their corresponding angles are equal and the ratios of all pairs of corresponding sides are equal. The ratio image side length / original side lenght is the scale by which all sides of the original figure "stretch or "shrink" into the corresponding sides of the image figure.
What I learned: I learned how to draw figures on a grid by completing a table and multiplying by numbers less than 1.
Methods and Strategies: If you first draw a pint on the grid connect it to the other one first keep connecting as you draw points because if you connect it at the last you would mess up, get confused and have to start all over again.
Problem 2.3
Use the table and dot paper grids on Labsheets 2.3A and 2.3B.
To make Mug's hat, plot points A-H from the Hat 1 column on the grid labeled Hat 1, connecting the points as you go.
For Hats 2-6, use the rulers in the table to fill in the coordinates for each column. Then, plot each hat on the appropriate grid, connecting the points as you go.
Problem 2.3 Follow Up
1. What rule would make a hat with line segments 1/3 the length of Hat 1's line segments?
0.3x, 0.3y.
2. What happens to a figure on a corrdinate grid when you add to or subtract from its coordinates?
The figure will move but the general shape will stay the same.
3. What rule would make a hat the same size as Hat 1 but moved up 2 units on the grid?
x, y+2.
4. What rule would make a hat with line segments twice as long as Hat 1's line segments and moved 8 units to the right?
2x+8, 2y.
NG
Big idea: Many things in our world are mathematically similar and we can use this to understand and describe the world around us.
Essential Question #2: What is the same and what is different about "similar" figures?
Vocabulary: Similar figures - Figures with the same shape. Two figures are mathematically similar if and only if their corresponding angles are equal and the ratios of all pairs of corresponding sides are equal. The ratio image side length / original side lenght is the scale by which all sides of the original figure "stretch or "shrink" into the corresponding sides of the image figure.
What I learned: I learned how to draw figures on a grid by completing a table and multiplying by numbers less than 1.
Methods and Strategies: If you first draw a pint on the grid connect it to the other one first keep connecting as you draw points because if you connect it at the last you would mess up, get confused and have to start all over again.
Problem 2.3
Use the table and dot paper grids on Labsheets 2.3A and 2.3B.
Problem 2.3 Follow Up
1. What rule would make a hat with line segments 1/3 the length of Hat 1's line segments?
0.3x, 0.3y.
2. What happens to a figure on a corrdinate grid when you add to or subtract from its coordinates?
The figure will move but the general shape will stay the same.
3. What rule would make a hat the same size as Hat 1 but moved up 2 units on the grid?
x, y+2.
4. What rule would make a hat with line segments twice as long as Hat 1's line segments and moved 8 units to the right?
2x+8, 2y.